Page 373 - Biaxial Multiaxial Fatigue and Fracture
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Three-Dimensional Crack Growth: Numerical Evaluations and Experimental Tests 357
hypotheses of linear elastic fracture mechanics (LEFM), which is not anymore applicable due to
the strong plasticity effects. The automatically created and updated mesh is based on a variable
number of quadratic elements: 512 initially and 758 at the last crack propagation step; it is
visible, together with Von Mises stresses in Figs. 17-18.
i
Fig. 18. Von Mises effective stresses on an magnified deformed plot of the plate (the part-
through crack opening is evident).
Through-crack propagation. After the crack breaks-out on the opposite side (with respect to the
notch position) of the plate, an initial scenario obtained from experimental measurements was
considered for the simulation. The related results are presented in Figs. 19-21. Again the
simulated propagation proceed a bit faster than the experimental one.
Again the crack front shapes foreseen by the simulation are well in agreement with the
experimental ones (Fig. 22).
Fig. 19. Von Mises effective stresses on an magnified deformed plot of the plate (the through
crack opening is evident).